Some Supplements Can Make You Fat
June 20, 2006
Adding vitamin supplements, including folic acid and vitamin B12, to the diet of pregnant mice caused their offsprings' weight to increase -- and the increase continued through generations.
Folic acid, vitamin B12 and certain similar vitamins add methyl groups to DNA, which impacts gene activity -- part of a new field known as epigenetics.
Previous research has found that methyl donors affect the gene activity of mice pups when added to the mother's diet, such as changing the coat color of mice with a mutation in a coat-color gene called agouti from yellow to brown.
Researchers say the supplements acted on the mice, known as agouti variable yellow or Ayy, by methylating a part of DNA that controls the coat-color gene.
The Ayy mice were also obese, and the researchers examined whether their weight could be affected by epigenetics. Ayy females were fed methyl-donating compounds including folic acid, vitamin B12, betaine and choline, in amounts similar to those received by humans taking vitamin supplements.
Weight Increased Over Generations
Although the researchers expected the pups' weight to decrease over generations as the methylation of the Ayy mutation increased, the mice gained weight over the generations. Non-Ayy mice showed a similar weight-gaining trend.
The findings bring in another dimension to how maternal nutrition could affect the human fetus, and add to the debate over whether pregnant women should increase their intake of folic acid, a supplement that's commonly used by expectant mothers to reduce the risk of spina bifida in newborns.